This invention relates to a tablet packing device which accommodates a plurality of types of tablets and selectively discharges them for packing, and a method for controlling the same.
A conventional "tablet packing machine" of this kind is disclosed in Examined Japanese Utility Model Publication 1-8482 in which tablet cases each accommodating one type of tablets are categorized into groups according to the distance from the packing position. A time required to transport a tablet from each tablet case to the packing sheet is preset for each tablet group. If a tablet is discharged from the tablet case, it is packed after the preset time specified therefor has lapsed. In this manner, the tablets are discharged from the tablet cases and packed without wasting time.
When tablets are let drop out of the tablet cases, some tablets leap out while others settle down quickly. For example, spherical soft capsules are likely to bounce, but elliptical capsules are not. Therefore, the bouncy capsules require a relatively long time to reach the packing sheet after discharged, but the capsules which settle down quickly take only a short time.
In such a conventional tablet packing device, the distance between the tablet case and the packing sheet is taken into a great consideration to cut the packing time, but no attention was paid to the tablet types. Namely, the time periods during which the dropped tablets reach the packing sheet are differentiated not according to the degree of bounce but according to the distance only. Should different types of tablets be transported for the same distance, the least bouncy tablet has to wait the longest time until it is packed. The time period is adjusted to the most bouncy tablet because it needs the longest time to settle down in comparison with others travelling the same distance.
It is an object of the present invention to provide a tablet packing device and a method for controlling it with which the time for a series of packing operations can be reduced.